退火温度对低温生长MgxZn1－xO薄膜光学性质的影响

用射频磁控溅射法在80℃衬底温度下制备出Mg_xZn_1-xO(x=0.16)薄膜，用X射线衍射(XRD)、光致发光(PL)和透射谱研究了退火温度对Mg_xZn_1-xO薄膜结构和光学性质的影响.测量结果显示，Mg_xZn_1-xO薄膜为单相六角纤锌矿结构，并且具有沿c轴的择优取向；随着退火温度的升高，(002)XRD峰强度、平均晶粒尺寸和紫外PL峰强度增大，(002)XRD峰半高宽(F 关键词： xZn_1-xO薄膜')" href="#">Mg_xZn_1-xO薄膜 射频磁控溅射 退火     

石英玻璃衬底上纤锌矿Mg0.25Zn0.75O薄膜的结构及光学性能

Mg_xZn_1-xO材料是一种新型光电功能材料.采用溶胶凝胶法在石英玻璃上制备了Mg_0.25Zn_0.75O薄膜,理论结合实验研究了Mg_0.25Zn_0.75O薄膜的结构和光学性能.研究表明,石英玻璃衬底上Mg_0.25Zn_0.75O薄膜呈六方纤锌矿结构,薄膜均匀,平均粒径约为20nm.吸收光谱表明吸收带边始于3 关键词： 0.25Zn_0.75O薄膜')" href="#">Mg_0.25Zn_0.75O薄膜 溶胶凝胶法 石英玻璃衬底 紫外发光     

溶胶-凝胶法制备MgxZn1-xO薄膜的结构及光学特性

用溶胶-凝胶法制备了一系列的Mg_xZn_1-xO(0≤x≤0.3)薄膜,并用X射线衍射(XRD)和光致发光(PL)研究了不同的退火温度和Mg的掺杂含量对Mg_xZn_1-xO薄膜的结构和光学性质的影响.研究表明:Mg_xZn_1-xO薄膜为单相六角纤锌矿结构,并且具有沿c轴的择优取向;发现了中间热处理温度为350℃的Mg_xZn_1-xO薄膜退火温度的转折点为700℃,低于这个温度时随退火温度的升高,(002)衍射峰强度增强且掺Mg的薄膜既有紫外光又有绿光发射;800℃退火时,薄膜的(002)衍射峰强度减小,出现了(100)和(101)衍射峰,且掺Mg的薄膜只有紫外发光峰.不同的掺杂浓度对于发光也有影响,低于700℃退火时,ZnO薄膜只出现紫外发光峰,掺Mg的薄膜却出现了紫外和绿光两个发光峰.     

射频磁控溅射法生长MgxZn1-xO薄膜的结构和光学特性

用射频磁控溅射法在80℃的衬底温度下制备出Mg_xZn_1-xO(0≤x ≤030)薄膜.x射线 衍射(XRD)结果表明，Mg_xZn_1-xO薄膜为单相六角纤锌矿结构， 没有形成任何显著 的MgO分离相，Mg_xZn_1-xO薄膜的择优取向平行于与衬底垂直的 c轴；c轴晶格常数随着Mg含量的增加逐渐减小.在Mg_xZn_1-xO薄膜的光透射谱中出现 锐利的吸收边，由透 射谱估算出Mg_xZn_1-xO薄膜的带隙宽度由332eV(x=0)线性地 增加到396eV(x=030). 关键词： xZn_1-xO薄膜')" href="#">Mg_xZn_1-xO薄膜 射频磁控溅射 Mg含量     

脉冲激光沉积(PLD)法生长高质量ZnO薄膜及其发光性能

采用脉冲激光沉积(PLD)法在单晶Si(100)衬底上生长ZnO薄膜,以X射线衍射(XRD)、原子力显微镜(AFM)和透射电镜(TEM)等手段分析了所得ZnO薄膜的晶体结构和微观形貌。优化工艺(700℃,20Pa)下生长的ZnO薄膜呈c轴高度择优取向,柱状晶垂直衬底表面生长,结构致密均匀。室温光致发光(PL)谱分析结果表明,随着薄膜生长时O₂分压的增大,近带边紫外发光峰与深能级发光峰之比显著增强,表明薄膜的结晶性能和化学计量比都有了很大的改善。O₂分压为20Pa时所生长的ZnO薄膜具有较理想的化学计量比和较高的光学质量。     

γ-LiAlO2上非极性ZnO薄膜制备及其光谱性质研究

利用激光脉冲沉积(PLD)技术在(302)γ-LiAlO₂衬底上成功生长了非极性的a面(1120) ZnO薄膜. 衬底温度为350℃时，薄膜是混合取向(a向和c向)，以c面ZnO为主，且晶粒尺寸分布很宽；提高温度达500℃，薄膜变为单一的(1120)取向，摇摆曲线半高宽0.65°，晶粒尺寸分布趋窄，利用偏振透射谱可以明显看出其面内的各向异性. 衬底温度650℃下制备的样品晶粒继续长大，虽然摇摆曲线半高宽变大，但光致发光谱(PL)带边发射峰半高宽仅为105meV，比在350℃，500℃下制备的样品小1/5. 关键词： 非极性ZnO 2')" href="#">γ-LiAlO₂ PLD 透射谱     

衬底温度对PLD法生长的Mg0.05Zn0.95O薄膜结构和发光特性的影响

用脉冲激光沉积(PLD)法在不同温度的Si(111衬底上成功制备了c轴择优取向的Mg0.05Zn0.95O薄膜.通过X射线衍射(XRD)和光致发光谱(PL)研究了衬底温度对Mg0.05Zn0.95O薄膜结构和发光特性的影响,探讨了膜的结晶质量与发光特性之间的关系.结果表明,在衬底温度为450℃时生长的Mg0.05Zn0.95O薄膜具有很好的轴取向和较强的光致发光峰.室温下分别用激发波长为240,300和325nm的氙灯作为激发光源得到不同样品的PL谱,分析表明紫外发光峰和紫峰来源于自由激子的复合辐射且发光强度与薄膜的结晶质量密切相关,蓝绿发光峰与氧空位有关.此外,探讨了衬底温度影响紫外光致发光峰红移和蓝移的可能机理.     

制备工艺对Zn1-xMgxO薄膜结构及光学性能的影响

采用脉冲激光沉积（PLD）方法在单晶Si（100）衬底上沿c轴方向生长单晶Zn_1-xMg_xO薄膜,通过X射线衍射（XRD）、原子力显微镜（AFM）、扫描电镜（SEM）和荧光光谱（PL）研究了膜厚、Mg含量、退火温度及氧气氛等制备工艺对Zn_1-xMg_xO薄膜的结构、形貌和光学性质的影响.实验结果表明,Mg含量x≤0.15时, Zn_{关键词： 1-x}Mg_xO薄膜')" href="#">Zn_1-xMg_xO薄膜 制备工艺 结构 光学性质     

Zn$lt;sub$gt;1-$lt;i$gt;x$lt;/i$gt;$lt;/sub$gt;Mg$lt;sub$gt;$lt;i$gt;x$lt;/i$gt;$lt;/sub$gt;O薄膜的光致发光特性研究

采用脉冲激光沉积方法在单晶Si（100）衬底上制备出c轴取向的Zn_1-xMg_xO单晶薄膜,通过荧光光谱仪研究了薄膜的光致发光特性.实验结果表明,Mg含量增加,Zn_1-xMg_xO单晶薄膜的紫外发光峰蓝移,发光峰强度减弱,缺陷发光强度增强.同时发现,由于Mg的掺杂,引入了一些束缚能较大的局域束缚态.对于氧气氛下制备的样品,实验发现紫外峰和绿光带发光峰同时增强,但是R值减小,紫外峰红移.对绿光发光机理研究发现,绿光发光带主要与锌空位、氧间隙（O_i）或锌位氧（O_Zn）等缺陷有关,它是由多个缺陷发光峰组成,各缺陷发光峰强度相对变化导致了绿光发光带的整体移动. 关键词： 1-xMg_xO薄膜')" href="#">Zn_1-xMg_xO薄膜 光致发光 脉冲激光沉积     

Pb(Zr0.3Ti0.7)O3铁电薄膜激光感生电压效应

采用脉冲激光沉积(PLD)技术在LaSrAlTaO₃(LSATO),LaAlO₃(LAO)和SrTiO₃(STO)的单晶倾斜衬底上成功制备了Pb(Zr_0.3Ti_0.7)O₃(PZT)薄膜,在三种倾斜衬底上生长的PZT薄膜中都首次发现了LIV效应.对PZT/LSATO薄膜在a,c轴两种不同取向择优生长下的LIV效应做了研究,发现在薄膜c轴取向择优生长 关键词： 激光感生电压效应 铁电薄膜 薄膜生长取向 原子层热电堆     

Effect of substrate temperature on the morphology, structural and optical properties of Zn1−xCoxO thin films

Zn_1−xCo_xO thin films with c-axis preferred orientation were deposited on sapphire (0 0 0 1) by pulsed laser deposition (PLD) technique at different substrate temperatures in an oxygen-deficient ambient. The effect of substrate temperature on the microstructure, morphology and the optical properties of the Zn_1−xCo_xO thin films was studied by means of X-ray diffraction (XRD), atomic force microscopy (AFM), UV-visible-NIR spectrophotometer, fluorescence spectrophotometer. The results showed that the crystallization of the films was promoted as substrate temperature rose. The structure of the samples was not distorted by the Co incorporating into ZnO lattice. The surface roughness of all samples decreased as substrate temperature increased. The Co concentration in the film was higher than in the target. Emission peak near band edge emission of ZnO from the PL spectra of the all samples was quenched because the dopant complexes acted as non-radiative centers. While three emission bands located at 409 nm (3.03 eV), 496 nm (2.5 eV) and 513 nm (2.4 eV) were, respectively, observed from the PL spectra of the four samples. The three emission bands were in relation to Zn interstitials, Zn vacancies and the complex of V_O and Zn_i (V_OZn_i). The quantity of the Zn interstitials maintained invariable basically, while the quantity of the V_OZn_i slightly decreased as substrate temperature increased.     

The optical properties of MgxZnl-xO thin films

Mg_xZn_1-xO thin films have been prepared on silicon substrates by radio frequency magnetron sputtering at 60℃. The thin films have hexagonal wurtzite single-phase structure and a preferred orientation with the c-axis perpendicular to the substrates. The refractive indices of Mg_xZn_1-xO films are studied at room temperature by spectroscopic ellipsometry over the wavelength range of 400--760\,nm at the incident angle of 70℃. Both absorption coefficients and optical band gaps of Mg_xZn_1-xO films are determined by the transmittance spectra. While Mg content is increasing, the absorption edges of Mg_xZn_1-xO films shift to higher energies and band gaps linearly increase from 3.24.eV at x=0 to 3.90\,eV at x=0.30. These results provide important information for the design and modelling of ZnO/ Mg_xZn_1-xO heterostructure optoelectronic devices.     

磁控共溅射法制备的Zn2GeO4多晶薄膜结构及其光致发光研究

用射频磁控共溅射方法在不同温度的单晶硅基片上生长薄膜,然后在800℃真空环境下对薄膜进行退火处理,成功获得了结晶状态良好的Zn₂GeO₄多晶薄膜.利用X射线衍射(XRD),X射线光电子能谱(XPS)和原子力显微镜(AFM)对薄膜进行了结构、成分和形貌分析,研究了基片温度对三者的影响. 结果显示,当基片温度升高到400℃以上时,薄膜中的Zn₂GeO₄晶粒在(220)方向上显示出了明显的择优取向. 当基片温度在500—600℃范围内,有利于GeO₂结晶相的形成. XPS显示薄膜中存在着Zn₂GeO₄,GeO₂,GeO,ZnO四种化合态. 同时,随着基片温度的升高,晶粒尺寸增大且薄膜表面趋于平整. 薄膜的光致发光在绿光带存在中心波长为530和550nm两个峰,应该归因于主体材料Zn₂GeO₄中两个不同的Ge²⁺的发光中心. 关键词： 射频磁控溅射 2GeO₄')" href="#">Zn₂GeO₄ 荧光体     

Optical properties of Mg<Subscript>0.05</Subscript>Zn<Subscript>0.95</Subscript>O/SiO<Subscript>2</Subscript> nanocomposite films prepared by sol–gel technique

Mg_0.05Zn_0.95O/SiO₂ nanocomposite films in the molar ratio 25:75 consisting of Mg_0.05Zn_0.95O nanoparticles embedded in a dielectric matrix were prepared by sol–gel technique (spin coating). Optical transmittance, Raman effect and photoluminescence measurements of the composites indicated effective capping of the Mg_0.05Zn_0.95O nanoparticles (radii 1. 61–1.68 nm) in the host showing practically no variation of particle size with the post deposition annealing treatments. The blue shift of the band gap (4.29–4.23 eV) from that of bulk Mg_0.05Zn_0.95O indicated strong carrier confinement for samples annealed at T ≤ 873 K. Highly intense UV emission ( ∼ 4.14 eV) compared to that of defect related emission (2.59 eV) at room temperature was obtained by incorporating 5% Mg in ZnO.This revised version was published online in August 2005 with a corrected issue number.     

Optical properties of Mg0.05Zn0.95O/SiO2 nanocomposite films prepared by sol–gel technique

Mg_0.05Zn_0.95O/SiO₂ nanocomposite films in the molar ratio 25:75 consisting of Mg_0.05Zn_0.95O nanoparticles embedded in a dielectric matrix were prepared by sol–gel technique (spin coating). Optical transmittance, Raman effect and photoluminescence measurements of the composites indicated effective capping of the Mg_0.05Zn_0.95O nanoparticles (radii 1. 61–1.68 nm) in the host showing practically no variation of particle size with the post deposition annealing treatments. The blue shift of the band gap (4.29–4.23 eV) from that of bulk Mg_0.05Zn_0.95O indicated strong carrier confinement for samples annealed at T ≤ 873 K. Highly intense UV emission ( ∼ 4.14 eV) compared to that of defect related emission (2.59 eV) at room temperature was obtained by incorporating 5% Mg in ZnO.     

Structural, optical and electrical properties of Zn1−xCdxO thin films prepared by PLD

Ternary polycrystalline Zn_1−xCd_xO semiconductor films with cadmium content x ranging from 0 to 0.23 were obtained on quartz substrate by pulse laser deposited (PLD) technique. X-ray diffraction measurement revealed that all the films were single phase of wurtzite structure grown on c-axis orientation with its c-axis lattice constant increasing as the Cd content x increasing. Atomic force microscopy observation revealed that the grain size of Zn_1−xCd_xO films decreases continuously as the Cd content x increases. Both photoluminescence and optical measurements showed that the band gap decreases from 3.27 to 2.78 eV with increasing the Cd content x. The increase in Cd content x also leads to the broadening of the emission peak. The resistivity of Zn_1−xCd_xO films decreases evidently for higher values of Cd content x. The shift of PL emission to visible light as well as the decrease of resistivity makes the Zn_1−xCd_xO films potential candidate for optoelectronic device.